The present invention relates generally to construction, excavation and/or other heavy machinery such as excavators, backhoes and the like that include an arm assembly comprising an arm or “stick” and a control link, each or which is adapted for pivotable connection to an associated attachment such as a bucket or other implement for performing work, and all such machines are referred to herein as “excavation apparatus” of “excavators.” The control link is operably coupled to a hydraulic cylinder or other actuator, and the position of the control link as controlled by the actuator controls the angular position of the attachment relative to the arm, i.e., extension and retraction of the control link results in curling and roll-back of the attachment, respectively.
To improve the utility and versatility of such excavation apparatus, it is most desirable that various implements be conveniently and reliably coupled to the arm. This, then, allows a single excavation apparatus to be employed with any one of a wide variety of attachments as desired. However, given the size and weight of the attachments, and the close tolerances of all connection points, changing of attachments at the end of the arm of an excavator has been found to be time-consuming, difficult and inconvenient.
In a most basic arrangement, the attachments are manually pinned to the excavator arm and any associated fluid cylinders. Such operation necessarily requires manual removal and replacement of multiple pins to achieve the desired engagement.
More recently, quick-coupler devices have been developed and have enjoyed widespread commercial success. One suitable coupling is commercially available from JRB Company, Inc., Akron, Ohio under the trademark SmartLoc™. Such quick-couplers are pivotally pinned to the distal end of the arm and control link in the same manner as an attachment. Once a quick-coupler is operatively pinned in position, first and second recesses thereof are adapted for selective connection to first and second pins of any of a wide variety of associated attachments in a convenient and secure manner without removal of the first and second pins.
Although these quick-couplers are highly effective and convenient, they add weight to the excavator arm and also elongate the arm, the combination of which can lead to a decrease in excavator performance in certain circumstances. The additional weight of the quick coupling can decrease the lifting capacity of the excavator. The outward movement of the attachment can also reduce lifting capacity and can change the performance characteristics of the attachment.
As such, a need has been identified for an attachment quick-coupling apparatus that provides the advantages of conventional quick-coupler apparatus without many of the drawbacks associated with same.